Magnetic flywheel and method of forming the same



Feb. 17, 1931. c. 1.. COUGHLIN 1,792,530

MAGNETIC FLY WHEEL AND METHOD OF FORMING THE SAME Filed Nov. 12, 1928 UMo W [hr/55 Z. I

Patented Feb. 17, 1931 UNITED STATES PATENT OFFICE CHARLES L. COIIGHLIN, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO BRIGGS AND STRATTON CORPORATION, OF MILWAUKEE, WISCONSIN, A CORPORATION OF DELA- WARE MAGNETIC FLYWHEEL AND METHOD OF FORIING THE SAME Application filed November 12, 1928. Serial N0.-318,71':

This invention relates to certain new and useful improvements in magnetic fly wheels and refers more particularly to that class of fly wheels which serve the double purpose of a fly wheel and a rotary field magnet fora magneto generator and has as an object the provision of an improved structure in which the magnetic bars and pole pieces have the fly wheel proper cast thereabout to form a substantially integral unit.

Another object of this invention resides in the provision of an improved magnetic fly wheel which is of simplified and inexpensive form and which eliminates the danger of the parts becoming loose in operation.

A further object of this invention resides in the provision of a magnetic fly wheel in which the magnet bars and pole pieces are welded or otherwise connected to form a unitary, substantially integral structure prior to the casting of the fly wheel thereabout.

And a still further, object of this invention resides in the provision of an improved method of forming a magnetic fly wheel whereby the necessity of riveting or otherwise connecting the parts is eliminated and the members forming the magnetic circuit having the fly wheel proper cast thereabout to form a one piece, substantially integral structure.

With the above and other objects in view which will appear as the description pro ceeds, my invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the herein disclosed invention may be made "as come within the scope of the claims.

In the accompanying drawing, I have illustrated one complete example of the physical embodiment of my invention constructed according to the best mode I have so far devised for the practical application of the principles thereof, and in which:

I Figure 1 is an inner side clevational view ofa magnetic fly wheel embodying this invention, parts thereof being broken away and in section to more clearly illustrate structural details; and

Figure 2 is a transverse, sectional view taken through Figure 1 on the plane of the line 22.

Referring now more particularly to the accompanying drawing, in which like numerals designate like parts throughout the several views, 5 represents segmental magnetic bars having their adjacent ends 6 slightly spaced to receive the material 7 built u in welding 21 pair of pole pieces 8 to the ad acent ends of the magnet bars so that the magnet bars and pole pieces are joined in a substantially integral unit.

The assembled. magnetic bars and pole pieces are then positioned in a suitable mould and the metal fly wheel 9 cast thereabout preferably by die casting, one face of the fly wheel being bored, as at 10, With the inner peripheral surface 11 of the pole pieces extended slightly beyond the wall 12 of the bore 10. In assembling, the coils and other stationary elements of the magneto, not shown, are confined within the bore 10 in the usual manner.

' The magnetic bars 5 and the pole pieces being welded together form a substantially integral structure and the metal fly wheel being cast thereabout produces a substantially one piece unit. v

The pole pieces 8 are preferably formed from cold drawn bar stock and are bent on an arc of less diameter than the desired finished diameter in order to insure the necessary electrical clearance between their ends 8 and the magnet bars, as shown in Figure 1.

What I claim as my invention is:

1. A magnetic fly wheel, comprising a pair of segmental magnet bars, polepieces con nected with the magnet bars at their adjacent ends, and a fly wheel cast about the bars and pole pieces and having a recess in one side with which the outer faces of the pole pieces communicate.

2. A magnetic fly wheel, comprising a pair of segmental magnet bars having their adjacent ends spaced, a pair of pole pieces, means rigidly connecting the ends of the magnet bars with each other to form a-substantially fly Wheel about the magnet bare and pole pieces, K

e, A magnetic fly wheel, comprising at pair of segmental magnet Boers, having their ends oonneoted to form a continuous homogeneous Icing diametrically opposite pole pieces havmg their medial portions integral with the said continuous homogeneous ring and their outer ends spaced from the inner periphery thereof and e fly wheel cast about said ring and poie pieces In testimony whereof 1 have hereunto effixed my signature.

' GHARLE$ L. COUGHLIN, 

